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Typical Campfire thread...

WGAF?!?!? If your groups are so bad you're worried about mean vs median, you got bigger problems!

Does this have anything to do with cankles?

I know nothink!

More concerned with my cold bore shot.

Aren't we all?

Amen...

WTF are cankles? That sounds like a question I don't want the answer to........

This thread is worthless without pictures. So....

I shoot three shot groups at one hundred yards and require multiple groups on the same outing to stay inside 1 1/2". If all is good I will go hunting. I do shoot some out to 300 yards at the range but work hard to keep my field shots inside 300. If I miss an opportunity (read do not take the shot), oh well, that's hunting. Most all I own will do better but it is from luck more than shooting the pizz out of the rifle to find the micro-load. Haven't had much trouble at all hitting stuff. Prior to my BC grizzly hunt I decided to give the 225 gr AB a go in my 338-06. First outing with VV-N550 and I was done. A lucky day.

Ten shots rapid fire from my AR off the bench.(Dot is 3/4".) Sometimes three shot groups are your friend, sometimes they are your enemy. Same could be said of any sample. If you only fired 3 shots and two of those happened to be the fliers in the pic below, you might think your gun was a turd. Pretty easy to conclude where this gun wants to shoot based on the other 8. That being said, who only shoots one 3 shot group to make a claim about accuracy? I usually shoot three shot groups, but shoot a lot of three shot groups before I conclude what a gun is capable of.

I prefer three shot groups with sporters also, wanting to see several at different ranges before I know it to be "the load". Even then, I've been known to foul up a group here and there with a flier, especially in the wind at 300-400yds. It's how the gun/load behaves most of the time that matters, as I'm honestly not as consistent as my equipment.

That being said, if I have the itch to try a new bullet or a new rifle and time is short, I'll hunt something that gives me a quick group or two at 1-1.5". Sometimes things don't have to be tweaked and tested to the max. It all depends on your goals.

Something to read on the subject: http://www.chuckhawks.com/practical_accuracy.htm

I don't agree with Hawk's logic:

"The hunter with a long range rifle capable of taking medium game at 300 yards (such as a 6mm Remington, .25-06, .270 Winchester, 7mm Remington Magnum or .300 Winchester Magnum), needs a rifle that averages 2 MOA groups. Those 2" groups at 100 yards will open to 6" at 300 yards. Very few hunters can take advantage of more accuracy than that in the field, so 2 MOA represents the practical limit of accuracy for most hunters. I am sure that Col. Whelen would have classified such a rifle as very "interesting." Of course, it is nice if Old Betsy will shoot even smaller groups at the rifle range, but it is simply not necessary from a practical standpoint."

He ignores the concept of error stacking. If my gun shoots 2 MOA, and I add 2 MOA of wiggle, all of a sudden I have 4 MOA groups, which would be 12" at 300 yds. Add another MOA of wind correction error, and things are that much worse.

I like to reasonably minimize the error my guns generate (like to be around 1 MOA or better) because I know I am going to add my own.

I wonder if the general benchmark of 1 moa would be different if 1 moa didn't conveniently work out as very near to 1 inch at 100 yards?

We do like symmetry and even numbers don't we?

For those of us that use metric, I am afraid 25.4mm at 91 metres doesn't quite have the same ring to it!

No, but 30 mm at 100 meters gets real close.. .143" at 109.4 yards.

Utah,

In my experience the largest "error stacking" with most hunters an handloaders is caused by depending on 3-shot groups as the accuracy standard of their rifle and ammo.

The reason most see so many "fliers" at 300 yards is because 3-shot groups are inadequate. This is easily demonstrated by shooting several 3-shot groups at 100 yards, each on a different target, but putting each target up in the same position over a blank sheet of paper. The result of all those 3-shot groups will be a far better demonstration of the rifle's actual accuracy.

Partly that's because it's rare to see anybody put out wind flags on a range. In the past five years, in fact, I've seen exactly one other shooter use wind flags at the one semi-public range I use. Without shooting groups of more than three shots AND using wind flags, any claims about MOA rifles are theoretical--as are notions about what's required to consistently hit a deer in the lungs at 300 yards.

I feel like a voice crying in the wilderness....one more time: Variation does not stack linearly. This is not intuitively obvious. In fact, it is the opposite of intuitively obvious. Yet it has very important consequences for firearm accuracy.



This is exactly how practically everyone interprets the situation. However, reality is actually more kind to the shooter.

If your firearm has 2 MOA of wiggle, and you have 2 MOA of wiggle, and there is no wind your wiggles will stack up to 2.8 MOA rather than 4 MOA. If the wind adds another 1 MOA of wiggle, your groups are 3 MOA.

More realistically, if you have 4 MOA of shooter wiggle, and your gun has 2 MOA of wiggle, your groups will be 4.5 MOA. The difference between a 2 MOA gun and a 0 MOA (perfect) gun in this case is a trifle under .5 MOA.

If one of the sources of variation is larger than the rest, it alone almost completely determines the total variation. That is why you have to find the single largest source, and kill it, rather than than fiddle with the lesser sources of variation which will make almost no contribution to total variation.

John is correct in his statements about 3 shot groups. A single 3 shot group has very little predictive power as to what the next group of shots will look like.

I think part of the problem is psychological. Somebody shoots dozen groups, figures that the best of them truly represents the gun, and that the poorer groups were the result of some kind of shooter error. If the shooter does everything perfectly every time, there will still be substantial variation in group size. A single group of (for example) 3 or 5 shots is a poor indicator of future performance. If you shoot enough groups, even the worst sewer pipe barrel will occasionally produce a .5 MOA group.

I agree with what Denton says,although I could never explain as articulately.I typically shoot groups a 100 yards to get a feel for things and to zero.I then usually go to 300 yards and shoot field prone(no rear bag and over a pack or some other object).

I have been doing things this way for years because there are no front and rear bags in the field.

Over the years I have shot many groups ranging from 2-4 inches at that distance,and it has not mattered greatly if the rifle was a 5/8" tack driver, or a 1.5 inch rifle for 3 shots at 100 (although sometimes I will shoot 8-10 shots from a rifle at 100 if it is new to me).But over the years,I've determined that I should be able to "hold" into about an MOA under those conditions

To be perfectly honest, if I missed the lungs of a deer at 300-400 yards with even a 2 MOA rifle, I would be very surprised.

The fact that MD, Denton and Bob know what they are writing about can easily be proven with two .22lr rifles. One that shoots excellent and one that shoots average.

Dial them in at 50 yards, adjust the sights for 75 or 100yards and then start shooting pop/soda cans, clay targets or resulting pieces of clay targets from field positions. Day-in, day-out the hit ratio difference will be very small if any.

The issue with "groups" is that the first shot is always a freebie as all one shot groups are equal. For a hunting rifle, the first shot is the most important. How close to point of aim a rifle/shooter can place that first shot and how close to point of aim all the subsequent shots hit means more to me than "group size".

I put a new barrel on my AR last week and finally had things dry out enough to fine tune the bipod/no rear bag zero at 100yds shooting the 70gr VLD.

Dots were shot from bottom left to top right.
After first 3 shot string scope was adjusted down 1/3 MOA
After second 3 shot string scope was adjusted left 1/4 MOA
I lost some focus on the middle 2 strings.



While the "group size" of the middle targets was not horrible the high shots stand out and show more of a shooter issue and not a rifle issue.

In other words I think I get more feedback per shot on both my shooting and the rifle by shooting to the point of aim than just shooting a "group" somewhere on the paper.